1. Field of Invention
The present invention relates to a recombinant adenovirus, and more particularly to the recombinant adenovirus co-expressing the humanized monoclonal antibody variable region gene of anti proto-oncogene neu/erbB2 and the Mda-7/IL-24 gene.
2. Description of Related Arts
The researches show that the proto-oncogene neu/erbB2 is a main mark gene of many kinds of malignant tumors, which is also called malignant protein. The neu/erbB2 gene is in an over-expressing state in about 30% of the patients suffering breast cancer and in partial patients with other cancers, such as ovarian cancer, lung cancer, and gastric cancer, which is one of the main reasons that these tumors become malignant and metastasis.
Some countries have successfully developed the humanized monoclonal antibody against the proto-oncogene neu/erbB2. The humanized monoclonal antibody against the proto-oncogene neu/erbB2, which has been approved by FDA, exists in the current market and the clinical applications showing that the humanized monoclonal antibody can effectively treat the malignant breast cancer and has been clinically approved. (Carter P, et al: PNAS, 1992, 4285-4289; Stebbing. J., et al: Cancer Treat. Reviews 2000; 26:287-290). Although the humanized monoclonal antibody can effectively treat malignant breast cancer with over-expressing the proto-oncogene, the clinical researches show that a resistance to the antibody occurs within one year in most of the patients with metastatic breast cancer being effectively treated via the antibody, and 15% of the patients will have relapse. Therefore, combining other medicine or other therapies is the main objective for increasing the effectiveness of the antibody and overcoming the resistance to the antibody when treating breast cancer over expressing the neu/erbB2 by the antibody (Tseng P H, et al: Mol Pharmacol. 2006 November; 70(5):1534-41; Nahta R, et al: Breast Cancer Res. 2006; 8(6): 215).
In addition, the researches also show that the application of variable region of the humanized monoclonal antibody not only has function of the antibody, but also increase penetration of the therapeutic antibody into tumors and its residence time in tumor tissue and blood. (Gregory P, et al: Cancer Research 1993, 53:4026-4034; Adams G P, et al: Brit. J Cancer (1998); 77(9): 1405-1412). The above built a firmly foundation for the drug treatment of single-chain variable region or Fab fragment of the monoclonal antibody.
Recently, the pegylated Fab fragment of tumor necrosis factor antibody has been proved due to its effectively control of the rheumatoid arthritis and chronic colitis, and approved by the United States FDA for the clinical applications, which show that monoclonal antibody single-chain variable region or Fab fragment used as a drug for treatment is practical.
In the recent years, the melanoma differentiation associated (mda) gene applied on clinical assessment, also called interleukin (IL-24), is one of the members of the interleukin-10 family. Mda-7/IL-24 gene is a conservative gene in structure. The expression product of the Mda-7/IL-24 gene is saddle-glycoprotein composed via 206 amino acids, wherein the saddle-glycoprotein is able to induce the interleukin-6, interferon-γ, tumor necrosis factor alpha, interleukin-1β, interleukin-12, and granulocyte macrophage colony-stimulating factor to express (Devanand Sarkar, et al: PNAS, 2005. 105(39): 14034-14039), so as to have multiple anti-tumor effect. Multiple tumor animal model experiments proof that the Mda-7/IL-24 has the ability of distinguish between normal cells and tumor cells, being able to induce the apoptosis function of the tumor cells, to inhibit the formation of tumor angiogenesis and tumor growth, to regulate immune responses, and to increase the sensitivity of tumor cell to chemical drugs, and biological agents, while has no significant poison effect on normal cells. So Mda-7/Il-24 is a specific tumor apoptosis factor having a cytokines of dual role, wherein the normal physiological function of Mda-7/IL-24 may be related to immune system, and the over expressing of the Mda-7/IL-24 may lead the apoptosis of specific tumor cells (Fisher P B, et al: Cancer Biol Ther. 2003 July-August; 2(4Suppl 1): S23-37; Fisher P B et al: Curr Gene Ther. 2006 February; 6(1): 73-91; Gupta P, et al: Pharmacol Ther. 2006 September; 111(3): 596-628. Epub 2006 Feb. 7). So far, the efficacy of clinical assessment is being satisfied. In the clinical assessment of advanced adenocarcinoma patients it is proved the safety and well tolerant. The intratumoral injection is able to kill the tumor cells via the cell apoptosis.
In some other countries, the clinical researches has confirmed treatment of the malignant breast cancer via the humanized monoclonal antibody combining with the Mda-7/IL-24 is more effective than using the humanized monoclonal antibody only, or combining with the chemotherapy, and may also kill the metastasized tumor cells (Bocangel D, et al: Cancer Gene Ther. 2006 October; 13(10): 958-68).
As the above mentioned researches and clinical assessments, to build a recombinant adenovirus co-expressing variable region gene of the humanized antibody and Mda-7/IL-24 gene for a more effective treatment of malignancy of overexpressing proto-oncogene neu/erbB2 is feasible.